Condensation of 3-(2-bromoacetyl)coumarins 1
with various 2-aminopyridines 2 in
the solid state under solvent-free conditions yield 3-imidazo[1,2-]pyridin-2-yl-chromen-2-ones
3. Condensation of 1 with 2-methylpyridines in dry benzene
affords N-alkylpyridinium salts 5.
These undergo cyclization reaction when heated with sodium bicarbonate to give
indolizines 6. The structures of
newly prepared compounds have been confirmed from analytical and spectral data.
Some of the compounds exhibit antitubercular, antiviral and anticancer
activities.